================================================================== BUG: KASAN: use-after-free in hlist_move_list include/linux/list.h:729 [inline] BUG: KASAN: use-after-free in __collect_expired_timers kernel/time/timer.c:1339 [inline] BUG: KASAN: use-after-free in collect_expired_timers kernel/time/timer.c:1569 [inline] BUG: KASAN: use-after-free in __run_timers+0xa2e/0xb90 kernel/time/timer.c:1616 Write of size 8 at addr ffff8801cdc83840 by task syz-executor0/28950 CPU: 0 PID: 28950 Comm: syz-executor0 Not tainted 4.14.0-rc5+ #139 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:52 print_address_description+0x73/0x250 mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report+0x25b/0x340 mm/kasan/report.c:409 __asan_report_store8_noabort+0x17/0x20 mm/kasan/report.c:435 hlist_move_list include/linux/list.h:729 [inline] __collect_expired_timers kernel/time/timer.c:1339 [inline] collect_expired_timers kernel/time/timer.c:1569 [inline] __run_timers+0xa2e/0xb90 kernel/time/timer.c:1616 run_timer_softirq+0x4c/0xb0 kernel/time/timer.c:1646 __do_softirq+0x2d7/0xb85 kernel/softirq.c:284 invoke_softirq kernel/softirq.c:364 [inline] irq_exit+0x1cc/0x200 kernel/softirq.c:405 exiting_irq arch/x86/include/asm/apic.h:638 [inline] smp_apic_timer_interrupt+0x177/0x710 arch/x86/kernel/apic/apic.c:1059 apic_timer_interrupt+0x9d/0xb0 arch/x86/entry/entry_64.S:770 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:777 [inline] RIP: 0010:rmqueue mm/page_alloc.c:2853 [inline] RIP: 0010:get_page_from_freelist+0x2613/0x3400 mm/page_alloc.c:3172 RSP: 0000:ffff880194ce6dd0 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff10 RAX: dffffc0000000000 RBX: 0000000000000004 RCX: 0000000000000006 RDX: 1ffffffff0b58c71 RSI: 1ffff1003a0131ac RDI: 0000000000000282 RBP: ffff880194ce74b8 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: ffffea0005ea8000 R12: 0000000000000000 R13: dffffc0000000000 R14: ffffed003299ce12 R15: ffff880194ce7490 __alloc_pages_nodemask+0x588/0xd80 mm/page_alloc.c:4197 __alloc_pages include/linux/gfp.h:469 [inline] __alloc_pages_node include/linux/gfp.h:482 [inline] alloc_pages_vma+0x30b/0x4b0 mm/mempolicy.c:1994 do_huge_pmd_anonymous_page+0x376/0x1b00 mm/huge_memory.c:722 create_huge_pmd mm/memory.c:3802 [inline] __handle_mm_fault+0x1827/0x39c0 mm/memory.c:4005 handle_mm_fault+0x334/0x8d0 mm/memory.c:4071 __do_page_fault+0x5bd/0xd60 arch/x86/mm/fault.c:1444 do_page_fault+0xee/0x720 arch/x86/mm/fault.c:1520 page_fault+0x22/0x30 arch/x86/entry/entry_64.S:1066 RIP: 0033:0x4056d0 RSP: 002b:0000000000a6f910 EFLAGS: 00010246 RAX: 000000002001d000 RBX: 0000000000000002 RCX: 0000000000000002 RDX: 4b51c29e880a1b69 RSI: 0000000000000000 RDI: 00000000014b4848 RBP: 0000000000000000 R08: 0000000000000000 R09: 00000000000000d9 R10: 0000000000a6f9b0 R11: 0000000000000246 R12: fffffffffffffffe R13: 000000002001d000 R14: 00000000000351d3 R15: 0000000000000010 Allocated by task 28473: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551 __do_kmalloc_node mm/slab.c:3689 [inline] __kmalloc_node+0x47/0x70 mm/slab.c:3696 kmalloc_node include/linux/slab.h:535 [inline] kvmalloc_node+0x64/0xd0 mm/util.c:397 kvmalloc include/linux/mm.h:529 [inline] kvzalloc include/linux/mm.h:537 [inline] alloc_netdev_mqs+0x16e/0xed0 net/core/dev.c:8023 tun_set_iff drivers/net/tun.c:2024 [inline] __tun_chr_ioctl+0x12b2/0x3d20 drivers/net/tun.c:2278 tun_chr_ioctl+0x2a/0x40 drivers/net/tun.c:2523 vfs_ioctl fs/ioctl.c:45 [inline] do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:685 SYSC_ioctl fs/ioctl.c:700 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:691 entry_SYSCALL_64_fastpath+0x1f/0xbe Freed by task 28473: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3503 [inline] kfree+0xca/0x250 mm/slab.c:3820 kvfree+0x36/0x60 mm/util.c:416 netdev_freemem net/core/dev.c:7975 [inline] free_netdev+0x2cf/0x360 net/core/dev.c:8137 tun_set_iff drivers/net/tun.c:2107 [inline] __tun_chr_ioctl+0x2cea/0x3d20 drivers/net/tun.c:2278 tun_chr_ioctl+0x2a/0x40 drivers/net/tun.c:2523 vfs_ioctl fs/ioctl.c:45 [inline] do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:685 SYSC_ioctl fs/ioctl.c:700 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:691 entry_SYSCALL_64_fastpath+0x1f/0xbe The buggy address belongs to the object at ffff8801cdc80500 which belongs to the cache kmalloc-16384 of size 16384 The buggy address is located 13120 bytes inside of 16384-byte region [ffff8801cdc80500, ffff8801cdc84500) The buggy address belongs to the page: page:ffffea0007372000 count:1 mapcount:0 mapping:ffff8801cdc80500 index:0x0 compound_mapcount: 0 flags: 0x200000000008100(slab|head) raw: 0200000000008100 ffff8801cdc80500 0000000000000000 0000000100000001 raw: ffffea000766ea20 ffffea00074be420 ffff8801dac02200 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801cdc83700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801cdc83780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8801cdc83800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801cdc83880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801cdc83900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================